The alternating current input is rectified and filtered to become direct current.
By controlling the switch tube with a high-frequency PWM (Pulse Width Modulation) signal, the direct current is applied to the primary winding of the switch transformer.
The secondary of the switch transformer induces a high-frequency voltage, which is then rectified and filtered to supply the load.
Output is fed back to the control circuit through a specific circuit, adjusting the PWM duty cycle to achieve stable output.
During the input of AC power, it generally passes through devices like chokes to filter out interference from the power grid, as well as to reduce the interference caused by the power supply to the grid.
At the same power, the higher the switching frequency, the smaller the volume of the switching transformer, but the higher the requirements for the switching tube.
Secondary windings of a transformer can have multiple turns or a single turn with multiple taps to achieve the desired output.
